const TextEditorRegistry = require('../src/text-editor-registry')
const TextEditor = require('../src/text-editor')
const TextBuffer = require('text-buffer')
const { Point, Range } = TextBuffer
const dedent = require('dedent')

describe('TextEditorRegistry', function () {
  let registry, editor, initialPackageActivation

  beforeEach(function () {
    initialPackageActivation = Promise.resolve()

    registry = new TextEditorRegistry({
      assert: atom.assert,
      config: atom.config,
      grammarRegistry: atom.grammars,
      packageManager: { deferredActivationHooks: null }
    })

    editor = new TextEditor({ autoHeight: false })
    expect(
      atom.grammars.assignLanguageMode(editor, 'text.plain.null-grammar')
    ).toBe(true)
  })

  afterEach(function () {
    registry.destroy()
  })

  describe('.add', function () {
    it('adds an editor to the list of registered editors', function () {
      registry.add(editor)
      expect(editor.registered).toBe(true)
      expect(registry.editors.size).toBe(1)
      expect(registry.editors.has(editor)).toBe(true)
    })

    it('returns a Disposable that can unregister the editor', function () {
      const disposable = registry.add(editor)
      expect(registry.editors.size).toBe(1)
      disposable.dispose()
      expect(registry.editors.size).toBe(0)
      expect(editor.registered).toBe(false)
      expect(retainedEditorCount(registry)).toBe(0)
    })
  })

  describe('.observe', function () {
    it('calls the callback for current and future editors until unsubscribed', function () {
      const spy = jasmine.createSpy()
      const [editor1, editor2, editor3] = [{}, {}, {}]
      registry.add(editor1)
      const subscription = registry.observe(spy)
      expect(spy.calls.length).toBe(1)

      registry.add(editor2)
      expect(spy.calls.length).toBe(2)
      expect(spy.argsForCall[0][0]).toBe(editor1)
      expect(spy.argsForCall[1][0]).toBe(editor2)
      subscription.dispose()

      registry.add(editor3)
      expect(spy.calls.length).toBe(2)
    })
  })

  describe('.build', function () {
    it('constructs a TextEditor with the right parameters based on its path and text', async function () {
      await atom.packages.activatePackage('language-javascript')
      await atom.packages.activatePackage('language-c')

      atom.config.set('editor.tabLength', 8, { scope: '.source.js' })

      const editor = registry.build({
        buffer: new TextBuffer({ filePath: 'test.js' })
      })
      expect(editor.getTabLength()).toBe(8)
    })
  })

  describe('.maintainConfig(editor)', function () {
    it('does not update the editor when config settings change for unrelated scope selectors', async function () {
      await atom.packages.activatePackage('language-javascript')

      const editor2 = new TextEditor()

      atom.grammars.assignLanguageMode(editor2, 'source.js')

      registry.maintainConfig(editor)
      registry.maintainConfig(editor2)
      await initialPackageActivation

      expect(editor.getRootScopeDescriptor().getScopesArray()).toEqual([
        'text.plain.null-grammar'
      ])
      expect(editor2.getRootScopeDescriptor().getScopesArray()).toEqual([
        'source.js'
      ])

      expect(editor.getEncoding()).toBe('utf8')
      expect(editor2.getEncoding()).toBe('utf8')

      atom.config.set('core.fileEncoding', 'utf16le', {
        scopeSelector: '.text.plain.null-grammar'
      })
      atom.config.set('core.fileEncoding', 'utf16be', {
        scopeSelector: '.source.js'
      })

      expect(editor.getEncoding()).toBe('utf16le')
      expect(editor2.getEncoding()).toBe('utf16be')
    })

    it('does not update the editor before the initial packages have loaded', async function () {
      let didActivateInitialPackagesCallback

      registry = new TextEditorRegistry({
        assert: atom.assert,
        config: atom.config,
        grammarRegistry: atom.grammars,
        packageManager: {
          deferredActivationHooks: [],

          onDidActivateInitialPackages (callback) {
            didActivateInitialPackagesCallback = callback
          }
        }
      })

      atom.config.set('core.fileEncoding', 'utf16le')

      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getEncoding()).toBe('utf8')

      atom.config.set('core.fileEncoding', 'utf16be')
      await initialPackageActivation
      expect(editor.getEncoding()).toBe('utf8')

      didActivateInitialPackagesCallback()
      await initialPackageActivation
      expect(editor.getEncoding()).toBe('utf16be')
    })

    it("updates the editor's settings when its grammar changes", async function () {
      await atom.packages.activatePackage('language-javascript')

      registry.maintainConfig(editor)
      await initialPackageActivation

      atom.config.set('core.fileEncoding', 'utf16be', {
        scopeSelector: '.source.js'
      })
      expect(editor.getEncoding()).toBe('utf8')

      atom.config.set('core.fileEncoding', 'utf16le', {
        scopeSelector: '.source.js'
      })
      expect(editor.getEncoding()).toBe('utf8')

      atom.grammars.assignLanguageMode(editor, 'source.js')
      await initialPackageActivation
      expect(editor.getEncoding()).toBe('utf16le')

      atom.config.set('core.fileEncoding', 'utf16be', {
        scopeSelector: '.source.js'
      })
      expect(editor.getEncoding()).toBe('utf16be')

      atom.grammars.assignLanguageMode(editor, 'text.plain.null-grammar')
      await initialPackageActivation
      expect(editor.getEncoding()).toBe('utf8')
    })

    it("preserves editor settings that haven't changed between previous and current language modes", async function () {
      await atom.packages.activatePackage('language-javascript')

      registry.maintainConfig(editor)
      await initialPackageActivation

      expect(editor.getEncoding()).toBe('utf8')
      editor.setEncoding('utf16le')
      expect(editor.getEncoding()).toBe('utf16le')

      expect(editor.isSoftWrapped()).toBe(false)
      editor.setSoftWrapped(true)
      expect(editor.isSoftWrapped()).toBe(true)

      atom.grammars.assignLanguageMode(editor, 'source.js')
      await initialPackageActivation
      expect(editor.getEncoding()).toBe('utf16le')
      expect(editor.isSoftWrapped()).toBe(true)
    })

    it('updates editor settings that have changed between previous and current language modes', async function () {
      await atom.packages.activatePackage('language-javascript')

      registry.maintainConfig(editor)
      await initialPackageActivation

      expect(editor.getEncoding()).toBe('utf8')
      atom.config.set('core.fileEncoding', 'utf16be', {
        scopeSelector: '.text.plain.null-grammar'
      })
      atom.config.set('core.fileEncoding', 'utf16le', {
        scopeSelector: '.source.js'
      })
      expect(editor.getEncoding()).toBe('utf16be')

      editor.setEncoding('utf8')
      expect(editor.getEncoding()).toBe('utf8')

      atom.grammars.assignLanguageMode(editor, 'source.js')
      await initialPackageActivation
      expect(editor.getEncoding()).toBe('utf16le')
    })

    it("returns a disposable that can be used to stop the registry from updating the editor's config", async function () {
      await atom.packages.activatePackage('language-javascript')

      const previousSubscriptionCount = getSubscriptionCount(editor)
      const disposable = registry.maintainConfig(editor)
      await initialPackageActivation
      expect(getSubscriptionCount(editor)).toBeGreaterThan(
        previousSubscriptionCount
      )
      expect(registry.editorsWithMaintainedConfig.size).toBe(1)

      atom.config.set('core.fileEncoding', 'utf16be')
      expect(editor.getEncoding()).toBe('utf16be')
      atom.config.set('core.fileEncoding', 'utf8')
      expect(editor.getEncoding()).toBe('utf8')

      disposable.dispose()

      atom.config.set('core.fileEncoding', 'utf16be')
      expect(editor.getEncoding()).toBe('utf8')
      expect(getSubscriptionCount(editor)).toBe(previousSubscriptionCount)
      expect(retainedEditorCount(registry)).toBe(0)
    })

    it('sets the encoding based on the config', async function () {
      editor.update({ encoding: 'utf8' })
      expect(editor.getEncoding()).toBe('utf8')

      atom.config.set('core.fileEncoding', 'utf16le')
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getEncoding()).toBe('utf16le')

      atom.config.set('core.fileEncoding', 'utf8')
      expect(editor.getEncoding()).toBe('utf8')
    })

    it('sets the tab length based on the config', async function () {
      editor.update({ tabLength: 4 })
      expect(editor.getTabLength()).toBe(4)

      atom.config.set('editor.tabLength', 8)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getTabLength()).toBe(8)

      atom.config.set('editor.tabLength', 4)
      expect(editor.getTabLength()).toBe(4)
    })

    it('enables soft tabs when the tabType config setting is "soft"', async function () {
      atom.config.set('editor.tabType', 'soft')
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getSoftTabs()).toBe(true)
    })

    it('disables soft tabs when the tabType config setting is "hard"', async function () {
      atom.config.set('editor.tabType', 'hard')
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getSoftTabs()).toBe(false)
    })

    describe('when the "tabType" config setting is "auto"', function () {
      it("enables or disables soft tabs based on the editor's content", async function () {
        await initialPackageActivation
        await atom.packages.activatePackage('language-javascript')
        atom.grammars.assignLanguageMode(editor, 'source.js')
        atom.config.set('editor.tabType', 'auto')
        await initialPackageActivation

        editor.setText(dedent`
          {
            hello;
          }
        `)
        let disposable = registry.maintainConfig(editor)
        expect(editor.getSoftTabs()).toBe(true)

        /* eslint-disable no-tabs */
        editor.setText(dedent`
          {
          	hello;
          }
        `)
        /* eslint-enable no-tabs */
        disposable.dispose()
        disposable = registry.maintainConfig(editor)
        expect(editor.getSoftTabs()).toBe(false)

        editor.setTextInBufferRange(
          new Range(Point.ZERO, Point.ZERO),
          dedent`
          /*
           * Comment with a leading space.
           */
        ` + '\n'
        )
        disposable.dispose()
        disposable = registry.maintainConfig(editor)
        expect(editor.getSoftTabs()).toBe(false)

        /* eslint-disable no-tabs */
        editor.setText(dedent`
          /*
           * Comment with a leading space.
           */

          {
          	hello;
          }
        `)
        /* eslint-enable no-tabs */
        disposable.dispose()
        disposable = registry.maintainConfig(editor)
        expect(editor.getSoftTabs()).toBe(false)

        editor.setText(dedent`
          /*
           * Comment with a leading space.
           */

          {
            hello;
          }
        `)
        disposable.dispose()
        disposable = registry.maintainConfig(editor)
        expect(editor.getSoftTabs()).toBe(true)
      })
    })

    describe('when the "tabType" config setting is "auto"', function () {
      it('enables or disables soft tabs based on the "softTabs" config setting', async function () {
        registry.maintainConfig(editor)
        await initialPackageActivation

        editor.setText('abc\ndef')
        atom.config.set('editor.softTabs', true)
        atom.config.set('editor.tabType', 'auto')
        expect(editor.getSoftTabs()).toBe(true)

        atom.config.set('editor.softTabs', false)
        expect(editor.getSoftTabs()).toBe(false)
      })
    })

    it('enables or disables soft tabs based on the config', async function () {
      editor.update({ softTabs: true })
      expect(editor.getSoftTabs()).toBe(true)

      atom.config.set('editor.tabType', 'hard')
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getSoftTabs()).toBe(false)

      atom.config.set('editor.tabType', 'soft')
      expect(editor.getSoftTabs()).toBe(true)

      atom.config.set('editor.tabType', 'auto')
      atom.config.set('editor.softTabs', true)
      expect(editor.getSoftTabs()).toBe(true)
    })

    it('enables or disables atomic soft tabs based on the config', async function () {
      editor.update({ atomicSoftTabs: true })
      expect(editor.hasAtomicSoftTabs()).toBe(true)

      atom.config.set('editor.atomicSoftTabs', false)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.hasAtomicSoftTabs()).toBe(false)

      atom.config.set('editor.atomicSoftTabs', true)
      expect(editor.hasAtomicSoftTabs()).toBe(true)
    })

    it('enables or disables cursor on selection visibility based on the config', async function () {
      editor.update({ showCursorOnSelection: true })
      expect(editor.getShowCursorOnSelection()).toBe(true)

      atom.config.set('editor.showCursorOnSelection', false)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getShowCursorOnSelection()).toBe(false)

      atom.config.set('editor.showCursorOnSelection', true)
      expect(editor.getShowCursorOnSelection()).toBe(true)
    })

    it('enables or disables line numbers based on the config', async function () {
      editor.update({ showLineNumbers: true })
      expect(editor.showLineNumbers).toBe(true)

      atom.config.set('editor.showLineNumbers', false)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.showLineNumbers).toBe(false)

      atom.config.set('editor.showLineNumbers', true)
      expect(editor.showLineNumbers).toBe(true)
    })

    it('sets the invisibles based on the config', async function () {
      const invisibles1 = { tab: 'a', cr: false, eol: false, space: false }
      const invisibles2 = { tab: 'b', cr: false, eol: false, space: false }

      editor.update({
        showInvisibles: true,
        invisibles: invisibles1
      })
      expect(editor.getInvisibles()).toEqual(invisibles1)

      atom.config.set('editor.showInvisibles', true)
      atom.config.set('editor.invisibles', invisibles2)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getInvisibles()).toEqual(invisibles2)

      atom.config.set('editor.invisibles', invisibles1)
      expect(editor.getInvisibles()).toEqual(invisibles1)

      atom.config.set('editor.showInvisibles', false)
      expect(editor.getInvisibles()).toEqual({})
    })

    it('enables or disables the indent guide based on the config', async function () {
      editor.update({ showIndentGuide: true })
      expect(editor.doesShowIndentGuide()).toBe(true)

      atom.config.set('editor.showIndentGuide', false)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.doesShowIndentGuide()).toBe(false)

      atom.config.set('editor.showIndentGuide', true)
      expect(editor.doesShowIndentGuide()).toBe(true)
    })

    it('enables or disables soft wrap based on the config', async function () {
      editor.update({ softWrapped: true })
      expect(editor.isSoftWrapped()).toBe(true)

      atom.config.set('editor.softWrap', false)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.isSoftWrapped()).toBe(false)

      atom.config.set('editor.softWrap', true)
      expect(editor.isSoftWrapped()).toBe(true)
    })

    it('sets the soft wrap indent length based on the config', async function () {
      editor.update({ softWrapHangingIndentLength: 4 })
      expect(editor.getSoftWrapHangingIndentLength()).toBe(4)

      atom.config.set('editor.softWrapHangingIndent', 2)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getSoftWrapHangingIndentLength()).toBe(2)

      atom.config.set('editor.softWrapHangingIndent', 4)
      expect(editor.getSoftWrapHangingIndentLength()).toBe(4)
    })

    it('enables or disables preferred line length-based soft wrap based on the config', async function () {
      editor.update({
        softWrapped: true,
        preferredLineLength: 80,
        editorWidthInChars: 120,
        softWrapAtPreferredLineLength: true
      })

      expect(editor.getSoftWrapColumn()).toBe(80)

      atom.config.set('editor.softWrap', true)
      atom.config.set('editor.softWrapAtPreferredLineLength', false)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getSoftWrapColumn()).toBe(120)

      atom.config.set('editor.softWrapAtPreferredLineLength', true)
      expect(editor.getSoftWrapColumn()).toBe(80)
    })

    it('allows for custom definition of maximum soft wrap based on config', async function () {
      editor.update({
        softWrapped: false,
        maxScreenLineLength: 1500
      })

      expect(editor.getSoftWrapColumn()).toBe(1500)

      atom.config.set('editor.softWrap', false)
      atom.config.set('editor.maxScreenLineLength', 500)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getSoftWrapColumn()).toBe(500)
    })

    it('sets the preferred line length based on the config', async function () {
      editor.update({ preferredLineLength: 80 })
      expect(editor.getPreferredLineLength()).toBe(80)

      atom.config.set('editor.preferredLineLength', 110)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getPreferredLineLength()).toBe(110)

      atom.config.set('editor.preferredLineLength', 80)
      expect(editor.getPreferredLineLength()).toBe(80)
    })

    it('enables or disables auto-indent based on the config', async function () {
      editor.update({ autoIndent: true })
      expect(editor.shouldAutoIndent()).toBe(true)

      atom.config.set('editor.autoIndent', false)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.shouldAutoIndent()).toBe(false)

      atom.config.set('editor.autoIndent', true)
      expect(editor.shouldAutoIndent()).toBe(true)
    })

    it('enables or disables auto-indent-on-paste based on the config', async function () {
      editor.update({ autoIndentOnPaste: true })
      expect(editor.shouldAutoIndentOnPaste()).toBe(true)

      atom.config.set('editor.autoIndentOnPaste', false)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.shouldAutoIndentOnPaste()).toBe(false)

      atom.config.set('editor.autoIndentOnPaste', true)
      expect(editor.shouldAutoIndentOnPaste()).toBe(true)
    })

    it('enables or disables scrolling past the end of the buffer based on the config', async function () {
      editor.update({ scrollPastEnd: true })
      expect(editor.getScrollPastEnd()).toBe(true)

      atom.config.set('editor.scrollPastEnd', false)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getScrollPastEnd()).toBe(false)

      atom.config.set('editor.scrollPastEnd', true)
      expect(editor.getScrollPastEnd()).toBe(true)
    })

    it('sets the undo grouping interval based on the config', async function () {
      editor.update({ undoGroupingInterval: 300 })
      expect(editor.getUndoGroupingInterval()).toBe(300)

      atom.config.set('editor.undoGroupingInterval', 600)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getUndoGroupingInterval()).toBe(600)

      atom.config.set('editor.undoGroupingInterval', 300)
      expect(editor.getUndoGroupingInterval()).toBe(300)
    })

    it('sets the scroll sensitivity based on the config', async function () {
      editor.update({ scrollSensitivity: 50 })
      expect(editor.getScrollSensitivity()).toBe(50)

      atom.config.set('editor.scrollSensitivity', 60)
      registry.maintainConfig(editor)
      await initialPackageActivation
      expect(editor.getScrollSensitivity()).toBe(60)

      atom.config.set('editor.scrollSensitivity', 70)
      expect(editor.getScrollSensitivity()).toBe(70)
    })

    describe('when called twice with a given editor', function () {
      it('does nothing the second time', async function () {
        editor.update({ scrollSensitivity: 50 })

        const disposable1 = registry.maintainConfig(editor)
        const disposable2 = registry.maintainConfig(editor)
        await initialPackageActivation

        atom.config.set('editor.scrollSensitivity', 60)
        expect(editor.getScrollSensitivity()).toBe(60)

        disposable2.dispose()
        atom.config.set('editor.scrollSensitivity', 70)
        expect(editor.getScrollSensitivity()).toBe(70)

        disposable1.dispose()
        atom.config.set('editor.scrollSensitivity', 80)
        expect(editor.getScrollSensitivity()).toBe(70)
      })
    })
  })
})

function getSubscriptionCount (editor) {
  return (
    editor.emitter.getTotalListenerCount() +
    editor.tokenizedBuffer.emitter.getTotalListenerCount() +
    editor.buffer.emitter.getTotalListenerCount() +
    editor.displayLayer.emitter.getTotalListenerCount()
  )
}

function retainedEditorCount (registry) {
  const editors = new Set()
  registry.editors.forEach(e => editors.add(e))
  registry.editorsWithMaintainedConfig.forEach(e => editors.add(e))
  registry.editorsWithMaintainedGrammar.forEach(e => editors.add(e))
  return editors.size
}
